Hospital beds are well known in the art. One type of hospital bed is an articulating bed. Another type of hospital bed is an expandable width bed. Expandable width beds generally include an expandable frame and supplemental mattress sections therewith. While such articulating and expandable width beds according to the prior art provide a number of advantageous features, they nevertheless often have certain limitations, including possibly having undesirable gaps between various sections of the mattress and/or between various supplemental mattress sections. Such undesirable gaps may be present in standard hospital beds as well. The present invention seeks to overcome certain of these limitations and other drawbacks of the prior art, and to provide new features not heretofore available. A full discussion of the features and advantages of the present invention is deferred to the following detailed description, which proceeds with reference to the accompanying drawings.